In order to achieve high thrust density and low thrust ripple simultaneously, a multiobjective optimization design method is applied to ironless permanent magnet linear synchronous motor with non-overlapping windings. On the basis of the magnetic field analysis model, the analytical formulae of key parameters such as No-load back EMF, thrust per copper quality and thrust ripple was deduced. Further, a multiobjective optimization is carried out by genetic algorithm to search for the optimal design variables. The design optimization is verified by 2-D Finite Element analysis and experimental results of the prototype.